Electrical circuits in residential and commercial buildings are often controlled by toggle switches. These toggle switches comprise an arm which is pivoted normally between an on position (upward) and an off position (downward). This switch may be located close to the load controlled by the switch, or may be significantly remotely located from such load.
When an electrician or other worker performing operations on the load or on the load side of the electric circuit therefor, safety requires that the switch controlling that circuit be in an off position and maintained in its off position. Although the circuit breaker for that circuit may be deactivated to provide greater safety, deactivating the circuit breaker would disrupt significantly more circuits than would be necessary, needlessly disrupting use of other load devices.
Inadvertent actuation of the switch to its on position while work is being performed on the load side of the circuit can cause injury to the worker and damage to the circuit and load equipment. Thus, the switch needs to be securely maintained in its off position while the work is being performed.
A number of different safety devices have been provided for both toggle electrical switches and for circuit breakers having a toggle switch mechanism. Typical examples are disclosed in U.S. Pat. No. 3,170,050 to Buturuga, U.S. Pat. No. 4,468,544 to Wainess, U.S. Pat. No. 4,876,425 to Woskow, U.S. Pat. No. 4,467,152 to Gordy, U.S. Pat. No. 4,506,120 to Fleischman, U.S. Pat. No. 4,733,029 to Kobayashi, U.S. Pat. No. 4,882,426 to Hovanic and U.S. Pat. No. 5,148,910 to Williams. However, these devices are not simple to make and use, and do not provide an adequately secure mechanism for preventing inadvertent actuation of the switch. For example, many of these devices are made up of multiple pieces or parts which increase the difficulty for manufacture. Many of the devices can be switched to the off position by manually manipulating device the guard, without removing the guard device from the face plate. These devices also require complete removable of the face plate mounting screws to mount the safety device on the face plate, complicating installation and increasing the likelihood of losing the face plate mounting screws, and thereby discouraging its use.